Most people who want a website for their business / project / publication / self want a site that does approximately 6 things: displays text, displays photos, displays videos, has a contact form, shows a map, and has a calendar. If this describes you, you do not want to hire a web developer. I'm not even saying that a developer is not worth the extra cost; I'm saying you'll be actively better off making a site yourself with one of the simple do-it-yourself site-builders*
*I mean, sure, unless you're so rich that you can hire a really good web developer to basically work full-time for you and be at your bidding 24 hours a day. If so, congrats!, your life sounds great
By analogy... imagine you're outfitting a set of offices and you need to buy some furniture. All the furniture you're looking for is really standard stuff: chairs, tables, book cases, desks. Now sure, you could go find an artisan to hand-craft furniture for you... but, aside from the higher price, you're then stuck in a situation where every time you need to make changes to your office you have to call back the artisan and ask her to come back in and shave 2 inches off the desk/build you two new chairs/change the design of the bookcase.
Alternatively, you could go to Ikea and buy a bunch of flat-pack furniture. When you need to raise or lower the desk there's an obvious way to do that. When you need more chairs you can know where to get them. There's 20 different designs that generally look good and you can pick the one that suits the look you're going for. And, of course, the joy of doing digital-stuff is that it's even better than Ikea: you can have as many new chairs as you want FOR FREE, and you can change the design of the whole room at the drop of a hat whenever you want to.
By contrast, if you hire a web developer then whenever you need to make changes you have to call her and wait till she has time to change X or do Y, even if X and Y are tiny things. Sure, most web developers will make you a site on something like Wordpress where, in theory, you're able to make changes yourself.... but Wordpress (though great!) is really not built to be something that you can just play with at will and figure out on your own how to make the changes you want. Wordpress is like a craft kit for a hobbyist furniture-maker: it might be 1000 times easier than doing the work from scratch, but it's not really sometihng you can just jump into and make arbitrary changes without trying.
And this is all without mentioning the really bad case, where your "web developer" turns out to be useless or has terrible taste or disappears on you and stops replying to your emails and leaves you stranded with a semi-working website that doesn't do what you want it to.
There's a bunch of simple site-builders out there now -- the one I've used most, and would broadly recommend, is Squarespace. They've put a lot of effort into making a site-builder that anyone can use, and their support-by-email is really good and really fast. Site-builders like Squarespace are designed to be "what you see is what you get" and have intuitive interfaces – if you've figured out how to lay out a document in Microsoft Word you'll be able to figure out how to use Squarespace just by poking around at it. Everything largely works how you expect it to.
I should state explicitly here that Squarespace is not some kind of Magical Site Of Brilliance. It's not a product that I L*O*V*E and want to Evangelise -- I think a better site-building site is definitely possible, and when I find it I'll recommend that instead -- but it does everything a normal person needs and it's not crazy-expensive and it works straightforwardly. You can make nice sites on it with no experience and a little bit of effort.
If you're starting a publication then you're in a slightly different boat – your website is your product, and you might think that's good reason to hire a web-developer to get your site looking picture-perfect. But even in that case, the best-looking publications I've seen online are invariably built with either GRID or Atavist. If I was starting a publication these days my first port of call would be to use one of those.
So who does need a web developer? Well... I started off by saying that most people who want a website only need it to do six things (text, photos, videos, contact forms, maps, calendars). And a simple site-builder will doubtless have tools to do other things too: quizzes, audio, FAQs, e-commerce, what have you. But at some point if what you're doing is sufficiently unusual and complicated then, sure, you need a web developer. Until then, though, save your money and time and make your website yourself. Like your granddad would have done, if he made websites.
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